Photobiocatalytic Synthesis of Biogenic Olefines
Robert Kourist, Marius Grote, Ioannis Zachos, Ruhr-Universität Bochum,  
Bochum, Germany
 
TDecarboxylases are emerging as sustainable catalytic tools for C-C bond breaking under mild reaction conditions. A recently discovered bacterial decarboxylase (FAD) catalyses the conversion of fatty acids into terminal olefins in aqueous systems and at room temperature [1]. FAD uses the peroxide shunt, in which hydrogen peroxide directly forms the catalytically active oxoferryl species that is required for breaking the C-C bond. While hydrogen peroxide is an inexpensive reagent, it is known to reduce the operational stability of enzymes. A viable synthetic alternative is the in situ generation of hydrogen peroxide. The steady supply at a low concentration allows conducting biocatalytic reactions without impairing the enzyme stability. In this study, we chose photocatalysis  [2] as inexpensive and robust method for H2O2 generation. Using cell-free extracts containing a recombinant fatty acid decarboxylase, the photobiocatalytic system proved to be efficient for olefine synthesis. 
The photobiocatalytic decarboxylation proved to be an efficient catalytic system for the decarboxylation of ω-functionalized fatty acids with a high functional group tolerance. The resulting α,ω-alkenols and α,ω-vinylcarboxylic acids are precursors for the synthesis of bio-based polymers. The poster discusses the combination of the OleT-catalyzed decarboxylation with other enzymatic and chemical transformations for the synthesis of bio-based fragrance compounds and diols. 

[1] Rude, M. A.; Baron, T. S.; Brubaker, S.; Alibhai, M.; Del Cardayre, S. B.; Schirmer, A. Appl. Environ. Microbiol. 2011, 77, 1718.
[2] I. Zachos, S.K. Gaßmeyer, D. Bauer, V. Sieber, F. Hollmann, Robert Kourist, (2015) Chem. Commun., 51, 1918-1921.